It is probably an Oncidium. There are many Oncidiums with Tolumnia-like flowers, but the distinguishing feature of Tolumnias is a lack of pseudobulbs.
You can post a picture by
1) clicking "go advanced"
2) scrolling down to "additional options"
3) clicking "manage attachments"
4) clicking "choose file" and selecting a file
5) clicking "upload"
This should work since you have more than 5 posts (which I think is the minimum number of posts needed in order to upload an image). If you've already followed these steps before, try using another browser.
